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Melymuk L.,Masaryk University | Goosey E.,University of Toronto | Goosey E.,University of Leicester | Riddell N.,Wellington Laboratories Inc. | Diamond M.L.,University of Toronto
Analytical and Bioanalytical Chemistry

Flame retardants (FRs) have come under considerable scientific and public scrutiny over the past decade. A lack of reference materials and standardized analytical methods has resulted in questions regarding the variation of measurements from different studies. We evaluated this variation by performing an international interlaboratory study assessing analytical capabilities as well as the accuracy and precision of results for a range of flame retardants (International Flame Retardant Laboratory Study, INTERFLAB). Thirteen international research laboratories participated in a blind interlaboratory comparison of 24 FRs. Results demonstrate good precision within replicates of test mixtures from individual laboratories, but problematic accuracy for several FRs and laboratories. Large ranges in the values reported for decabromodiphenylethane (DBDPE), tris(1,3-dichloropropyl)phosphate (TDCIPP), tetrabromobisphenol-A (TBBPA), and hexabromocyclododecane (HBCD) (>50 % relative standard deviations among measured values) and large deviations from the reference values (>25 % bias in accuracy) suggest potential problems for comparability of results. DBDPE, HBCD, and TBBPA had significantly poorer accuracy and precision, suggesting that current analytical methods are not providing reliable results for these FRs. © 2015 Springer-Verlag Berlin Heidelberg Source

Sundstrom M.,University of Stockholm | Bogdanska J.,University of Stockholm | Pham H.V.,University of Stockholm | Athanasios V.,University of Stockholm | And 5 more authors.

Here, we describe for the first time the synthesis of [ 35S] PFOS and [ 35S] PFBS with sulfur-35 enriched sulfur dioxide as the radiolabelled reagent, resulting in 2.5 and 2.3mCi of product, respectively. Basic information concerning the physicochemical properties of perfluorooctanesulfonate (PFOS), perfluorobutanesulfonate (PFBS) and perfluorooctanoic acid (PFOA) are still limited. Hence, we utilized these radiolabelled perfluoroalkanesulfonates (PFSAs), as well as carbon-14 labelled perfluorooctanoic acid ([ 14C] PFOA) to determine some basic characteristics of physiological and experimental significance. The solubility of PFOS in buffered aqueous solutions at pH 7.4 was found to be severely reduced in the presence of potassium and sodium ions, which, however, did not reduce the solubility of PFOA or PFBS. PFOS was found to adhere to a small extent to polypropylene and polystyrene, whereas no such adhesion of PFOA or PFBS was detected. The extents of adhesion of PFOS and PFOA to glass were found to be 20% and 10%, respectively. For the first time, the partition coefficients for PFOS, PFBS and PFOA between n-octanol and water were determined experimentally, to be -0.7, -0.3, and 1.4, respectively, reflecting the difference in the amphiphilic natures of these molecules. © 2012 Elsevier Ltd. Source

Black R.R.,University of Queensland | Mick Meyer C.P.,CSIRO | Yates A.,Australian National Measurement Institute | Van Zwieten L.,Wollongbar Primary Industries Institute | And 2 more authors.
Atmospheric Environment

The contribution of PCDD/PCDF emissions from soil during open burning of biomass was examined. Mass labelled PCDD/PCDF was added to soil containing native PCDD/PCDF and biomass was laid out on this soil and burnt, simulating sugarcane trash and forest fires. Smoke samples were collected using a high volume portable field sampler. After each fire the concentration of all mass labelled PCDD/PCDF congeners in the surface soil decreased, however, the concentration of some native 2,3,7,8 substituted congeners increased, indicating that formation was occurring. Mass labelled PCDD/PCDF congeners were detected in all ash samples, mean 2.8 pg g -1 (range 0.5-8 pg g -1), demonstrating release from the soil. Additionally, mass labelled PCDD/PCDF congeners were detected in all air samples mean 1.2 μg (t fuel) -1 (range 0.2-2.0 μg (t fuel) -1), again demonstrating release from the soil. Native 2,3,7,8 substituted congeners detected in the air samples were dominated (in terms of contribution to total congener mass) by Cl 8DD (90% for forest litter and 77% for sugarcane). The major contributor to TEQ of emissions from both forest litter and sugarcane was 1, 2, 3, 7, 8-Cl 5DD (40-64% and 57-75%, respectively). These results demonstrate that release of PCDD/PCDF from soil to air and land occurs during open burning of biomass when soil temperatures are sufficiently elevated. © 2012 Elsevier Ltd. Source

Jobst K.J.,Environment Canada | Shen L.,Environment Canada | Shen L.,Brock University | Reiner E.J.,Environment Canada | And 4 more authors.
Analytical and Bioanalytical Chemistry

Mass defect is the difference between the nominal and exact mass of a chemical element or compound. An intrinsic property of polyhalogenated molecules is a uniquely negative mass defect, which readily distinguishes halogenated from non-halogenated compounds in a complex mass spectrum and can be visualized by constructing a mass defect plot. This study demonstrates the utility of the mass defect plot as a powerful tool to screen gas-chromatography (ultra)high-resolution mass spectrometry data for potentially toxic and bioaccumulative halogenated compounds in a Lake Ontario lake trout, an apex species in the Great Lakes environment. Our results indicate that the sample is contaminated with polychlorinated biphenyls, terphenyls, diphenylethers, as well as other chlorinated pesticides and flame retardants that are regulated and routinely analyzed by traditional target analyses. However, the mass defect plot also displays peaks which could be traced to the presence of as yet undiscovered contaminants. These include chlorinated polycyclic aromatic hydrocarbons as well as mixed halogenated analogues of the flame retardant Dechlorane 604. The identity of the latter class of compounds is supported by experiments with genuine standards. [Figure not available: see fulltext.] © 2013 Springer-Verlag Berlin Heidelberg. Source

Shen L.,Brock University | Shen L.,Environment Canada | Jobst K.J.,Environment Canada | Helm P.A.,Environment Canada | And 7 more authors.
Analytical and Bioanalytical Chemistry

During the course of our studies of in-use chlorinated flame retardants, such as Dechlorane Plus® and Dechloranes 602 and 604, blubber of beluga whales from the Canadian Arctic and lake trout and whitefish from the North American Great Lakes were found to contain two novel dechlorination products of Dechlorane 602 (Dec602). The structures of these compounds were characterized by experiments performed using both gas chromatography-high resolution mass spectrometry and Fourier transform mass spectrometry with a prepared technical mixture of monohydro and dihydroDec602 derivatives. TheseDec602 derivatives are analogous to the well-known monohydro and dihydro photochemical degradation products of Mirex. The ratio of the two monohydroDec602 diastereomers varied between Lake Ontario fish and those from the upper lakes, but only one isomer was found in Arctic beluga, indicating that one isomer is either more stable or more bioaccumulative. Dechlorane Plus®, Dec603, and Dec 604 were not detected in Arctic beluga, but Dec602 and its monohydroDec602 derivative were measured in approximately equal concentrations, ranging from 25 to 300 pg/g lipid. In Great Lakes fish, concentrations of the monohydroDec602 derivatives were also close to those of Dec602, ranging from 2 to 67 ng/g lipid and were greatest in Lake Ontario. This study reports on the first measurements of dechlorane-related compounds inArctic biota and the first detection of monohydroDec602 degradation products and their accumulation in biota. © Springer-Verlag 2012. Source

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